Chemical functionalization of nanodiamond by amino groups: an X-ray photoelectron spectroscopy study.

The development of chemical functionalization techniques for diamond nanocrystallites opens up ways with a view to altering their solubility in different solvents, improve interfacial adhesion of nanodiamonds with a composite matrix in new materials, and provide new possibilities for the modification of the electronic properties of nanodiamond crystallites. In this work, we present results on the chemical functionalization of nanodiamonds by amino groups using ammonia as a nitrogenation agent. Nanodiamond material used was formed by the detonation technique with average crystallite sizes of 4-5 nm. The final materials and intermediates products were characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Chemical functionalization of nanodiamonds by amino groups could enable the preparation of new nylon nano-composite materials. Presence of surface amino groups could alter pH of nanodiamond colloids towards basic values and improve colloidal stability of nanodiamond suspensions at pH close to 7. This could enable syntheses of new drug delivery systems based on nanodiamonds.

Molecular basis for the regenerative properties of a secretion of the mollusk Cryptomphalus aspersa.

A screen for natural products bearing pharmacological properties has yielded a secretion of the mollusk Cryptomphalus aspersa (SCA), which possesses skin-regenerative properties. In this report, we outline some of the cellular and molecular effects underlying this observation. First, we found that SCA contained antioxidant SOD and GST activities. In addition, SCA stimulated fibroblast proliferation and rearrangement of the actin cytoskeleton. Additional mechanisms involved in the regenerative effect of SCA included the stimulation of extracellular matrix assembly and the regulation of metalloproteinase activities. Together, these effects provide an array of molecular mechanisms underlying SCA-induced cellular regeneration and postulate its use in regeneration of wounded tissue.

Phenolic components and antioxidant activity of Fernblock, an aqueous extract of the aerial parts of the fern Polypodium leucotomos.

Fernblock, an aqueous extract of the aerial parts of the fern Polypodium leucotomos, used as raw material for topical and oral photoprotective formulations, was fractioned by HPLC and the main components with antioxidant capability were identified by means of UV spectra, electrochemical detection, and MSn. Phenolic compounds were identified as 3,4-dihydroxybenzoic acid, 4-hydroxybenzoic acid, vanillic acid, caffeic acid, 4-hydroxycinnamic acid, 4-hydroxycinnamoyl-quinic acid, ferulic acid, and five chlorogenic acid isomers. Total ferric antioxidant capacity (FRAP) of HPLC eluted fractions was measured. The results suggest that the herein identified compounds support, at least partially, the antioxidant and radical scavenging capacities of Fernblock.

Polypodium leucotomos extract inhibits trans-urocanic acid photoisomerization and photodecomposition.

In this report, we demonstrate a possible molecular mechanism by which a hydrophilic extract of the leaves of the fern Polypodium leucotomos (Fernblock, PL) blocks ultraviolet (UV)-induced skin photodamage. The extract inhibits UVA and UVB light induced photoisomerization of trans-urocanic acid (t-UCA), a common photoreceptor located in the stratum corneum, and also blocks its photodecomposition in the presence of oxidizing reagents such as H2O2, and titanium dioxide (TiO2). PL protects in vitro human fibroblasts from UV-induced death as well. These results suggest the potential of employing the PL extract as a component of sunscreen moistures in order to prevent photodecomposition of t-UCA, to inhibit UV-induced deleterious effects of TiO2 and to protect skin cells and endogenous molecules directly involved in skin immunosurveillance.

Inmunoferon, an immunomodulator of natural origin, does not affect the rat liver cytochrome P-450 and phase II conjugation enzymes.

Inmunoferon is a glycoconjugate of natural origin with immunomodulatory properties. It has recently been shown to regulate TNF-alpha expression induced by lipopolysaccharide (LPS) challenge through a hypothalamo-pituitary-adrenal (HPA)-dependent mechanism. Inmunoferon is orally administered to immunocompromised patients as an adjuvant during immune therapy such as vaccination or infectious diseases treatment. Due to its mainly adjuvant nature, it is necessary to determine if coadministration of Inmunoferon affects the activity of other drugs. In this study we analyzed the possible modification of the hepatic drug biotransformation system by using Inmunoferon in a rat model, which may result in changes in the biological activity of other drugs administered simultaneously. Inmunoferon-treated animals showed no differences to control littermates in antipyrine metabolism. No differences were found in either cytochrome P-450 and b5 levels or cytochrome P-450-dependent activities and phase II conjugation enzymes in lysates from Inmunoferon-treated rat hepatic cells. The same treatment reduced levels of serum TNF-alpha in LPS-challenged animals. In summary, Inmunoferon is unable to affect the hepatic bioconjugation system during administration and thus seems unlikely to interact with, or modify the effect of, coadministered drugs.

Inmunoferon, a glycoconjugate of natural origin, regulates the liver response to inflammation and inhibits TNF-alpha production by an HPA axis-dependent mechanism.

In this report, we have examined the mechanism of action of Inmunoferon, a patented glycoconjugate (GC) of natural origin with immunomodulatory properties, in the regulation of TNF-alpha expression induced by LPS challenge in a rodent model. GC was found to be dependent on a normal HPA response to exert its regulatory effect on TNF-alpha expression. Adrenalectomized mice were unresponsive to the drug in terms of TNF-alpha levels after LPS challenge, whereas control mice showed lower serum TNF-alpha levels when treated with GC than vehicle-treated animals. GC treatment also induced the expression of acute phase proteins but it did not alter the normal metabolism or viability of hepatic cells. These data suggested the employment of GC as a novel adjuvant during antibacterial treatment without disadvantages such as side effects in the metabolism of the liver, thus, acting as an enhancer of the host response against infection.

Immunoferon, a glycoconjugate of natural origin, inhibits LPS-induced TNF-alpha production and inflammatory responses.

We have analyzed the effect of a patented glycoconjugate (GC) of natural origin, Inmunoferon, in the development of the response to endotoxemia induced by administration of LPS in rodents. We have observed that oral treatment with the drug reduced the levels of serum TNF-alpha induced by an intravenous pulse of LPS. The serum of pretreated mice blocked TNF-alpha production by peritoneal macrophages. The drug increased the levels of TNF-alpha regulators such as IL-10 and corticosteroids, whereas it inhibited TNF-alpha-dependent IL-6 production. Further TNF-alpha-dependent responses, such as cell extravasation, was decreased in treated mice. According to these results, Inmunoferon is postulated as an inhibitor of the systemic response to LPS. Correlation of the observations made in mice with a rat model suggests the efficacy of this product in reducing TNF-alpha production in a species-independent fashion and opens the possibility of its trial as an adjuvant of antibiotics in treatment against gram-negative bacterial infection.

A new method for radioiodination of polysaccharides and its use in biodistribution studies of an immunomodulating glycoconjugate (Immunoferon).

A new method for the labeling of polysaccharides by using tyrosine derivatives after CNBr activation is presented, along with its use for pharmacokinetic studies of an orally active immunomodulating noncovalent glycoconjugate, which was administered labeled either in the polysaccharide or the protein moiety. The relationship between the obtained results and the mechanism of action are also discussed.

Modalidades del uso de antibioticos en Concepcion, Chile / Adquisition and use of antibiotics in Concepcion, Chile

A survey to determine how 45 antibiotics dispensed to children and adults had been acquired and used was concluded in 27 pharmacies in Concepcion, Chile, based on sales with prescriptions (3 729 cases) and without prescriptions (2 959 cases). The data were compiled from August to December 1982 and from August to December 1983 by students who had completed their training at Conception University, School of Pharmacy, using a form on which they entered the age of the patient, the name of the antibiotic requested, the dosage form, the quantity dispensed, and the indications for its use. Average treatments observed were compared to reference standard treatments expressed as defined daily doses (DDD) for the prevalent pathologies. It was found that the main users were adults (68.3 per cent) most of whom presented no prescription (50.4 per cent); antibiotics were dispensed to children in most cases (69.2 per cent) under médical prescription. There was greater consumption of oral antibiotics (84.6. ) than of those for parenteral (11.8 per cent) or vaginal (3.5 per cent) administration. Compared with the standard treatment regimen (7 x DDD), treatments were generally found to be insufficient, particularly among adults who obtained oral antibiotics without a prescription. Respiratory infections were treated with antibiotics in more cases than any other disease

Rapid purification of the main allergen of Lolium perenne by high-performance liquid chromatography.

The main allergen from rye grass (Lolium perenne) pollen was purified by size-exclusion high-performance liquid chromatography. The purified allergen had a molecular weight of 32,000 daltons and was significantly more active in solid phase radioimmunoassay than the whole extract. The highly purified antigen can be obtained very rapidly and with a recovery of 30%.

Isolation and partial characterization of a monoclonal antibody specific for a naturally occurring double-stranded RNA.

A monoclonal antibody (Mab) against the double-stranded form of the cucumber mosaic virus-associated RNA 5, the sequence variant that induces the tomato necrosis disease (ds(n)CARNA 5), has been obtained. Specificity studies using a radioimmunoassay showed that the purified Mab recognizes neither DNA nor ssRNA of different sources including ss(n)CARNA 5, poly(I).poly(C), nor dsRNA of two other sequence variants of CARNA 5. Therefore, the Mab seems to recognize a conformational variation only present in the double helical structure of ds(n)CARNA 5.